1. Field of the Invention
The invention relates to a Universal Serial Bus (USB) receptacle, more particularly to a micro USB receptacle.
2. Description of the Related Art
Portable electronic products have a trend toward small size and light weight. Thus, the components of the portable electronic products are designed to be smaller and lighter to meet the requirement. As shown in FIGS. 1 and 2, a conventional USB receptacle 1 is adapted for use in a portable electronic product, such as a mobile phone, a personal digital assistant (PDA), a digital camera, or the like. The conventional USB receptacle 1 includes a housing 3 having a surrounding wall 31 that surrounds an axis (L) and that defines a receiving space 30 therein, and a terminal seat 2 extending into the housing 3 along the axis (L). The terminal seat 2 has a stop section 21, and a connecting section 22 that extends from the stop section 21 along the axis (L) and that has an axial length (D), and that is formed with a pair of spaced apart stop blocks 23. Each of the stop blocks 23 is formed with a stop surface 231 having a height (h). The housing 3 further has a pair of resilient plates 32, each of which extends obliquely relative to the axis (L) from the surrounding wall 31 into the receiving space 30, and has an end surface 321 (see FIG. 5).
As further shown in FIGS. 3 to 5, when assembling the conventional USB receptacle 1, the terminal seat 2 is extended into the housing 3 and is snap-fitted in the receiving space 30 in the housing 3 via the resilient deformation of the resilient plates 32 of the housing 3, such that the stop blocks 23 of the terminal seat 2 engage respectively the resilient plates 32 of the housing 3, and that the stop surface 231 of each of the stop blocks 23 confronts the end surface 321 of one of the resilient plates 32. When a force is applied to the housing 3 in the same direction as that in which the terminal seat 2 is extended into the housing 3, the end surface 321 of each of the resilient plates 32 abuts against the stop surface 231 of the corresponding one of the stop blocks 23, thereby preventing separation between the terminal seat 2 and the housing 3.
However, since the contact area between the end surface 321 of each of the resilient plates 32 of the housing 3 and the stop surface 231 of the corresponding one of the stop blocks 23 of the terminal seat 2 is relatively small, an application of a larger force to the housing 3 may ultimately result in separation between the housing 3 and the terminal seat 2. Moreover, the axial distance of the surrounding wall 31 of the housing 3 from one edge 311 thereof adjacent to the stop section 21 of the terminal seat 2 to where each of the resilient plates 32 extends has a minimum limitation of (D1) (see FIG. 4) so as to preserve the connecting strength between each of the resilient plates 32 and the surrounding wall 31, thereby obstructing the miniaturization of the conventional USB receptacle 1.
Although the previous first drawback can be overcome by enlarging each of the stop blocks 23 to result in a larger contact area between the end surface 321 of each of the resilient plates 32 and the stop surface 231 of the corresponding one of the stop blocks 23, the enlarged stop blocks 23 also increase the resistance with the resilient plates 32 and may even result in damage to the resilient plates 32 during the snap-fitting process between the terminal seat 2 and the housing 3. Besides, the housing 3 has to be made larger for accumulating the terminal seat 2 with the enlarged stop blocks 23, thereby also obstructing the miniaturization of the conventional USB receptacle 1.